JPH01116255A - Throttle valve opening and closing control mechanism - Google Patents

Abstract

PURPOSE:To enable emergency operation to be performed by closing a throttle valve by a closing mechanism and driving the throttle valve by the second actuator when an actuator, driving the throttle valve, is disabled to be controlled. CONSTITUTION:An intake pipe provides in its passage 2 a throttle valve 1 driven by a servomotor 4, and ordinarily a control unit controls the servomotor 4 so as to drive the throttle valve 1 to an optimum opening. In case of the servomotor 4 being disabled to be controlled, interrupting power to the servomotor 4 urging the throttle valve 1 in its closing direction by a return spring 5, a stopper part 3b, mounted to a turning shaft 3 of the throttle valve 1, is adapted to a linear solenoid 6, and the throttle valve 1 performs its emergency control by the linear solenoid 6.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an opening/closing control mechanism for a throttle valve used in an engine such as an automobile. This is what I did.

<Conventional technology> In recent years, gasoline engines installed in passenger cars, etc. have been electronically controlling the fuel supply amount, ignition timing, etc. in order to ensure engine performance such as output while preventing exhaust gas pollution and improving fuel efficiency. There are many things. Conventionally, the throttle valves of carburetors and electronic fuel injection systems were opened and closed in response to the driver's will via a cable directly connected to the accelerator pedal, but auto cruise (constant speed driving) devices With the development of automatic transmissions and mechanical automatic transmissions, some have appeared that employ an electronically controlled throttle valve opening/closing control mechanism driven by an electric actuator such as a servo motor.

In an electronically controlled throttle valve opening/closing control mechanism, a microprocessor normally processes various data such as the clutch engagement state and intake air temperature in addition to the amount of depression of the accelerator pedal, and controls the throttle valve according to the vehicle's current driving conditions. The optimum opening degree has been determined to correspond to the For this reason, for example, while the auto cruise device is operating, regardless of the load condition such as climbing,
It is easy to automatically adjust the opening of the throttle valve to maintain the vehicle speed at a set value, and to close the throttle valve regardless of the amount of pedal depression when disengaging the clutch in a mechanical automatic transmission. It is.

By the way, since the throttle valve must control the amount of intake air over the entire rotation range from start to high-speed running within its opening/closing stroke range, the increase/decrease in the flow path area with respect to the opening is large. Therefore, in order to improve fuel efficiency by reducing the engine speed to the verge of knocking during idling operation, very delicate opening/closing control is required in accordance with changes in intake air temperature, etc. For this reason, electronically controlled throttle valve opening/closing control mechanisms generally use a main actuator such as a servo motor, which is the first throttle valve drive means to drive the throttle valve from idle to full open, and a main actuator such as a servo motor to adjust the idle opening. An idle actuator such as a linear solenoid is provided as a second throttle valve driving means that slightly drives the throttle valve. During idle operation, the drive by the main actuator is stopped and the idle actuator activates the i!
This means that the degree of opening is obtained.

<Problem E that the invention seeks to solve> However, since this electronically controlled throttle valve opening/closing control mechanism has a complicated electronic control section, circuit breakage due to vibration, detour current due to fuse blowout, etc. Malfunction or stoppage of operation may occur due to radio wave interference caused by vehicle radio, etc., and the actuator itself that drives the throttle valve may burn out. Among these failures, failures on the idle actuator side are unlikely to cause serious problems due to their small drive range, but failures on the main actuator side can cause runaway accidents, for example, if the throttle valve is held in the fully open position. This is not to say that there is no concern that it will provoke.

won.

Means for Solving Problems> Therefore, the present invention provides a throttle valve that is provided in the passage of the intake pipe and increases or decreases the amount of intake air by opening and closing the throttle valve, and a first throttle valve that opens and closes the throttle valve when the throttle valve is not idle. A throttle valve opening/closing control mechanism comprising: a drive means; a second throttle valve drive means that drives the throttle valve to open and close during idle; a return mechanism that biases the throttle valve in the closing direction; and a return mechanism that biases the throttle valve in the closing direction. When the opening/closing control of the throttle valve by the driving means becomes impossible, the driving of the throttle valve by the first throttle valve driving means is stopped, and while the throttle valve is biased in the closing direction by the return mechanism, the second throttle valve is The engine is equipped with a control means for continuing operation of the engine by means of a throttle valve driving means.

In this throttle valve opening/closing control mechanism, when opening/closing control of the throttle valve by the first throttle valve driving means becomes impossible, the return mechanism biases the throttle valve in the closing direction and the second throttle valve is activated. The valve drive means opens and closes the valve to enable emergency engine operation.

Embodiments Examples of the throttle valve opening/closing control device according to the present invention will be described below.

Figures 1 and 2 schematically show a plane and a side view of the first embodiment, respectively.

In the figure, a butterfly-type throttle valve 1 is rotatably provided in a passage 2 of an intake pipe, and its rotation shaft 3 is connected to a first throttle valve driving means (main actuator).
It is connected to a barrel servo motor 4. Further, the end portion 3a of the rotating shaft 3 engages with a coil-shaped return spring 5 serving as a return mechanism, and is biased in the closing direction, and in the state shown in the figure, the locking portion 3b protruding in a T-shape The plunger 6a of the linear solenoid 6, which is the second throttle valve drive means (idle actuator), is in contact with the plunger 6a. and,
Both the servo motor 4 and the linear solenoid 6 are connected to a control unit (not shown), and are operated according to instructions from the control unit.

The control unit is connected to various sensors (also not shown) such as an accelerator position sensor, an air flow sensor, and a throttle valve opening sensor serving as a feedback means, as well as an auto-cruise device and the like.

The control unit includes an arithmetic processing unit that processes input data from these devices and determines the opening degree of the throttle valve 1, and a drive control unit that issues commands to the servo motor 4, linear solenoid 6, etc. have. Drive control is performed based on the accelerator opening during normal driving, but as mentioned above, when the auto cruise device is activated or the clutch is disengaged, the appropriate opening is instructed regardless of the accelerator opening. .

Now, when a failure occurs in the control unit or the servo motor 4 itself, and the opening/closing control of the throttle valve 1 by the servo motor 4 becomes impossible, the drive control section issues a command at the time of failure. The determination of uncontrollability is made based on various setting conditions, such as, for example, the throttle valve 1 is not fully opened within a predetermined time even though the accelerator opening is 0°.

In the case of this embodiment, the first command at the time of failure is the servo motor 4.
It is to stop energizing to. by this,
The throttle valve 1 is released from the servo motor 4, is rotated by the return spring 5 from a fully open state, and is returned to a position where it contacts the plunger 6a of the linear solenoid 6.

The second command in the event of a failure is to send a current proportional to the accelerator opening to the linear solenoid 6, and the plunger 6a
The purpose of the present invention is to enable the opening and closing of the throttle valve 1 to be driven by the throttle valve 1. However, the movable range of the plunger 6a is not set so that the throttle valve 1 opens too widely, but is limited to a range that allows the engine to be operated on an emergency basis. This is to ensure safety in the event that the linear solenoid 6 side, rather than the servo motor 4 side, fails.

Note that in this embodiment, the servo motor 4 and the throttle valve 1 are fixedly connected by the rotation shaft 3;
As shown in FIG. 3, an electromagnetic clutch 7 may be interposed between the servo motor 4 and the rotating shaft 3, and disconnected in the event of a failure. In this case, even when the servo motor 4 is stuck with the throttle valve 1 fully open, the return spring 5 can be easily operated, and the return spring S itself has a weak spring force because the mass of the servo motor 4 is no longer relevant. things become usable. Furthermore, in this embodiment, the beam near solenoid 6 is made to follow the accelerator opening only when the servo motor 4 fails, but it may also be made to operate in synchronization with the servo motor 4 within its movable range during normal times. good. In this case, the command issued by the control unit at the time of failure is only to stop driving the throttle valve 1 by the servo motor 4.

In the first embodiment, the return spring 5 is used as a return mechanism that biases the throttle valve 1 in the closing direction, and the biasing force is applied to the throttle valve 1 even in normal times. It is provided with a return mechanism that operates only at certain times to reduce the burden on the servo motor 4 due to the biasing force of the return spring 5 during normal times.

FIGS. 4 and 5 show examples of the return mechanism according to this embodiment. In FIG. 4, a coil-shaped actuator 8 made of bimetal, shape memory alloy, etc. is energized, and the throttle valve 1 is closed by its heat-generating deformation. Further, in FIG. 5, a coil spring 5 that closes the throttle valve 1 is locked by a fuse 9 when the throttle valve 1 is fully open, and this fuse 9 is blown by energizing, and the throttle valve 1 is moved in the closing direction. It is something that energizes.

In this embodiment, the throttle valve 1 is set to the plunge position of the linear solenoid 6 during normal operation. Since there is no return spring or the like to press against -6a, a weak current is passed through the servo motor 4 during idle operation to generate a biasing force in the closing direction.

In the case of this embodiment, since a biasing force such as a return spring does not act on the servo motor 4, a small, lightweight, and low-cost motor can be adopted.

In the above embodiments, a servo motor was used as the first throttle valve drive means, a linear solenoid was used as the second throttle valve drive means, and a coil spring or the like was used as the return mechanism, but the present invention is not limited to these. For example, a linear solenoid and a linkage may be used as the first throttle valve driving means, a step motor or the like may be used as the second throttle valve driving means, and a linear solenoid or the like may be used as the return mechanism. Furthermore, in the above embodiment, the second throttle valve drive means opens and closes the throttle valve in conjunction with the accelerator opening, but fast idle control is used to drive the throttle valve to open and close in an on-off manner. Good too. In any case, according to the present invention, when the first throttle valve drive means is unable to control the vehicle, the second throttle valve drive means can perform emergency operation, allowing self-propulsion to a repair shop or the like.

What is shown in FIG. 6 is a control system diagram of this embodiment, and the sensors that send data to the control unit include an air flow sensor, an accelerator position sensor, a throttle opening sensor, a vehicle speed sensor, an engine rotation speed sensor,
There is an idle switch, crank angle sensor, etc.
It is shown that control signals are sent from the control unit to the first throttle valve drive means, the second throttle valve drive means, as well as the igniter and the injector. Moreover, what is shown in FIG. 7 is a control flowchart of this embodiment, and shows the procedure in which failure control is activated when the throttle valve cannot be controlled by the first throttle valve driving means. This flowchart further shows that in this embodiment, if the throttle valve does not operate as instructed at the time of failure, fuel cut and ignition cut are performed to stop the engine.

<Effects of the Invention> According to the present invention, the return mechanism that urges the throttle valve in the closing direction is provided, and when the first throttle valve drive means cannot control the throttle valve drive, only the second throttle valve drive means can control the throttle valve. Since the throttle valve is driven, there is no fear of runaway due to loss of control of the throttle valve, and emergency operation to a repair shop or the like is possible.

[Brief explanation of the drawing]

1 and 2 are a schematic plan view and a side view, respectively, of a first embodiment of the throttle valve opening/closing control mechanism according to the present invention, and FIG. 3 is a schematic plan view and a side view of the servo motor and throttle valve rotation of the first embodiment. It is a schematic diagram when an electromagnetic clutch is provided between the moving shaft and the moving shaft. Further, FIGS. 4 and 5 are schematic diagrams each showing a second embodiment of the return mechanism according to the present invention. FIG. 6 is a control system diagram of the present invention, and FIG.
The figure is a control flowchart. In the figure, 1 is a throttle valve, 2 is an intake pipe passage, 3 is a rotating wheel, 4 is a servo motor, 5 is a return spring, 6 is a linear solenoid, 7 is an electromagnetic clutch, 8 is an actuator, and 9 is a fuse. Figure 4 Figure 5 Figure 6

Claims (1)

[Scope of Claims] A throttle valve that is provided in an intake pipe passage and increases or decreases the amount of intake air by opening and closing the throttle valve; a first throttle valve drive means that opens and closes the throttle valve when the valve is not idling; and a throttle valve that opens and closes the throttle valve when the valve is idling. A throttle valve opening/closing control mechanism comprising: a second throttle valve driving means for opening and closing; a return mechanism for biasing the throttle valve in the closing direction; and a throttle valve opening/closing control by the first throttle valve driving means. If the throttle valve becomes disabled, the first throttle valve drive means stops driving the throttle valve, and the second throttle valve drive means operates the engine while the return mechanism biases the throttle valve in the closing direction. A throttle valve opening/closing control mechanism characterized by comprising: a control means for continuing; and a throttle valve opening/closing control mechanism.